scholarly journals Intraspecific consistency and geographic variability in temporal trends of spring migration phenology among European bird species

2007 ◽  
Vol 35 ◽  
pp. 135-146 ◽  
Author(s):  
D Rubolini ◽  
AP Møller ◽  
K Rainio ◽  
E Lehikoinen
Author(s):  
George, M. Linz ◽  
Amy, E. Barras ◽  
Richard, A. Sawin ◽  
H. , Jeffrey Homan ◽  
David, L. Bergman ◽  
...  

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
D. Tommy King ◽  
Guiming Wang ◽  
Zhiqiang Yang ◽  
Justin W. Fischer

2013 ◽  
Vol 28 (1) ◽  
pp. 39-42 ◽  
Author(s):  
Christos Barboutis ◽  
Angelos Evangelidis ◽  
Triantaphyllos Akriotis ◽  
Thord Fransson

2015 ◽  
Author(s):  
John D Lloyd ◽  
Chris C Rimmer ◽  
Kent P McFarland

We analyzed temporal trends in mist-net capture rates of resident (n = 8) and overwintering Nearctic-Neotropical migrant (n = 3) bird species at two sites in montane broadleaf forest of the Sierra de Bahoruco, Dominican Republic, with the goal of providing quantitative information on population trends that could inform conservation assessments. We conducted sampling at least once annually during the winter months of January – March from 1997 – 2010. We found evidence of steep declines in capture rates for three resident species, including one species endemic to Hispaniola. Capture rate of Rufous-throated Solitaire (Myadestes genibarbis) declined by 3.9% per year (95% CL = 0%, 7.3%), Green-tailed Ground-Tanager (Microlegia palustris) by 6.8% (95% CL = 3.9%, 8.8%), and Greater Antillean Bullfinch (Loxigilla violacea) by 4.9% (95% CL = 0.9%, 9.2%). Two rare and threatened endemics, Hispaniolan Highland-Tanager (Xenolegia montana) and Western Chat-Tanager (Calyptophilus tertius), showed statistically significant declines, but we have low confidence in these findings because trends were driven by exceptionally high capture rates in 1997 and varied between sites. Analyses that excluded data from 1997 revealed no trend in capture rate over the course of the study. We found no evidence of temporal trends in capture rates for any other residents or Nearctic-Neotropical migrants. We do not know the causes of the observed declines, nor can we conclude that these declines are not a purely local phenomenon. However, our findings, along with other recent reports of declines in these same species, suggest that a closer examination of their conservation status is warranted. Given the difficulty in obtaining spatially extensive, long-term estimates of population change for Hispaniolan birds, we suggest focusing on other metrics of vulnerability that are more easily quantified yet remain poorly described, such as extent of occurrence.


PeerJ ◽  
2016 ◽  
Vol 3 ◽  
pp. e1541 ◽  
Author(s):  
John D. Lloyd ◽  
Christopher C. Rimmer ◽  
Kent P. McFarland

We analyzed temporal trends in mist-net capture rates of resident (n= 8) and overwintering Nearctic-Neotropical migrant (n= 3) bird species at two sites in montane broadleaf forest of the Sierra de Bahoruco, Dominican Republic, with the goal of providing quantitative information on population trends that could inform conservation assessments. We conducted sampling at least once annually during the winter months of January–March from 1997 to 2010. We found evidence of declines in capture rates for three resident species, including one species endemic to Hispaniola. Capture rate of Rufous-throated Solitaire (Myadestes genibarbis) declined by 3.9% per year (95% CL = 0%, 7.3%), Green-tailed Ground-Tanager (Microligea palustris) by 6.8% (95% CL = 3.9%, 8.8%), and Greater Antillean Bullfinch (Loxigilla violacea) by 4.9% (95% CL = 0.9%, 9.2%). Two rare and threatened endemics, Hispaniolan Highland-Tanager (Xenoligea montana) and Western Chat-Tanager (Calyptophilus tertius), showed statistically significant declines, but we have low confidence in these findings because trends were driven by exceptionally high capture rates in 1997 and varied between sites. Analyses that excluded data from 1997 revealed no trend in capture rate over the course of the study. We found no evidence of temporal trends in capture rates for any other residents or Nearctic-Neotropical migrants. We do not know the causes of the observed declines, nor can we conclude that these declines are not a purely local phenomenon. However, our findings, along with other recent reports of declines in these same species, suggest that a closer examination of their conservation status is warranted. Given the difficulty in obtaining spatially extensive, long-term estimates of population change for Hispaniolan birds, we suggest focusing on other metrics of vulnerability that are more easily quantified yet remain poorly described, such as extent of occurrence.


Western Birds ◽  
2021 ◽  
Vol 52 (4) ◽  
pp. 322-339
Author(s):  
Ryan S. Terrill ◽  
Christine A. Dean ◽  
John Garrett ◽  
Daniel J. Maxwell ◽  
Lauren Hill ◽  
...  

Avian migration is a spectacular phenomenon, representing the annual movements of billions of birds globally. Because the greatest diversity and numbers of birds migrate at night, opportunities to observe active migration are rare. At a number of localities in North America, however, observers can quantify movements of many typically nocturnal migrants during daylight where they continue after dawn. Such locations have provided much information about species-specific phenology, status, and orientation during migration. Localities where morning flights of land birds can be observed are unevenly distributed, however, and are little reported along the Pacific coast. Here we describe a novel location for the observation of spectacular morning flights of nocturnal migrants during spring migration at Bear Divide, in the western San Gabriel Mountains, Los Angeles County, California. In two years of informal surveys at the site, we have recorded at least one morning with an estimated ~13,500 individual birds passing. Our preliminary analyses suggest that the peak of a species’ migration at Bear Divide is correlated with the latitude of a species’ breeding, being later in the spring as that latitude increases. Our data from Bear Divide provide an independent perspective on migration as quantified by local radar. Further work at this locality may help inform our knowledge of migration phenology and population trends.


2017 ◽  
Vol 28 (3) ◽  
pp. 475-492 ◽  
Author(s):  
BEATRICE SICURELLA ◽  
VALERIO ORIOLI ◽  
GUIDO PINOLI ◽  
ROBERTO AMBROSINI ◽  
LUCIANO BANI

SummaryNetworks of protected areas (PAs) where human activities are allowed at different degrees are fundamental to ensure the long-term conservation of biological diversity and ecological processes. However, studies aimed at assessing their effectiveness, focusing on several species simultaneously are scarce. We assessed the effectiveness of the system of protected areas (PAs) of Lombardy, Northern Italy, in conserving bird populations by comparing the changes from 1992 to 2013 in the occurrence of 54 breeding bird species censused in areas classified in different protection categories, namely Nature Reserves (NRs), areas designed predominantly for the protection of nature; Regional Parks (RPs), naturally valuable areas where human activities, including intensive agriculture, are allowed; and non-protected areas (NPAs). Overall, occurrence of common birds increased in Lombardy in the last 20 years and farmland and long-distance migrants (LDMs), which suffered sharp declines at a continental scale, showed stable and increasing trends, respectively. These trends were, however, the balance between those of species whose occurrence markedly increased, and those of species that dramatically declined. Species occurred more often in PAs than in NPAs, while temporal trends in occurrence were significantly more positive in RPs than in both NRs and NPAs. Hence, PAs seemed effective in preserving common bird communities. Occurrence of woodland and short-distance migrant species was higher in PAs than in NPAs, while occurrence of farmland species and LDMs was similar in all protection categories. PAs of Lombardy appear therefore effective only in protecting some categories of birds. Farmland and LDM birds would benefit more from ecologically sustainable land-use policies aiming at improving agro-ecosystem biodiversity than from protected areas.


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